Hi! Yesterday I published MapBBCode plugin. It allows for embedding maps in forum posts with user-drawn lines and markers on them. You can test the underlying library on the official website (mapbbcode.org). There are many uses to it: planning and sharing routes, geolocating photos, pinpointing locations and so on. The plugin integrates with share.mapbbcode.org service: you can draw a single map and include it in multiple posts or even forums.

I cannot post links, so the address is cvs.prohost.org/index.php/Mapbbcode.plugin
The plugin itself is published on github (URL is on the wiki page).